Eye testing instrument



June 29, 1943. w. F. PECK ErAL EYE TESTING INSTRUMENT 12 Sheets-Sheet 1Original Filed April 6, 1939 |09 .m9 R Y *Q nmm- .TQ- m R t mx. VCS T swww T Q 2V Us. Il 6 Q Y 3N m ,uw Ma. w mm. 3 Q n.. U.. K m vw um 5 I @di 2 s s e J mm q Q u m Q .Y w3 o B e SN Q B m mJPS @A a, hws Nm, s s s lb N N t s m3 n @n AMM. s. s. .s s kw m HO 2 N E un 8. /w (E mom l 2N H Wl 3N EN QN .2N me June 29, 1943. w. F. Pl-:CK ETAL EYE TESTINGINSTRUMENT Original Filed April 6, 1939 l2 Sheets-Sheet 2 EN .nl RN June2 9, 1943.

Original Filed April 6, 1939 mi i rSJlI W. F. PECK ETAL EYE TESTINGINSTRUMENT 12 Sheets-Sheet .'5

June 29, 1943.

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EYE TESTING INSTRUMENT Y Original Filed April 6, 1939 12 SheetS-Sheet 4INVENTOR n//LL/HM E PECK L5/l1 H. 6.6/9 /S/ RNE June 29, 1943. w. F.PEcK ET AL EYE TESTING INSTRUMENT Original Filed April 6, 1939 12Sheets--Sl'leetl 5 INVENTOR WML/9M E PECK /uB//y n, GRH /JHR ATT NEYJune 29, i243. w. F. PECK ET AL 2,322,878

EYE TESTING INSTRUMENT original Filed April 6, 1939 l2 'sheets-sheet e Il m; l l

INVENTOR W/LL/HM f.' PECK BY /LB//Y l?. GRHD/SHR' June 29, 1943.l w. F.PEcK ET Al.

EYE TESTING INSTRUMENT Original Filed April 6, 1939 12 Sheets-Sheet '7II [Il Q A Nm @nm n@ Q mn w EN m, w3 .a p x R Y mm M ME VPE U m56. A 2%um L mw M Y B June 29, 1943. w. F. PECK i-:TAL

EYE TESTING INSTRUMENT Original Filed April 6, 1939 12 Sheets-Sheet 8INVENTOR MM E Pfck ,y a. swap/sea ffm V June 29, 1943. w. F. PECK ET ALEYE TESTING INSTRUMENT l2 sheets-sheet 9l original Filed April e, 1959INVENTOR i #wa/HM E PECK BY /iL//y fi. G/P/m/sme ATTZNEY QB m: o: QN..@EMS l @www w i @M mm, b3 mi ...l m2 ma l i sg .msg @www mm. E. @E NQ o@E .E m QQ June 29, 1943. w. F. PEcKE-rAL 2,322,378

EYE TESTING INSTRUMENT original Filed April e, 1939 l2 sheets-sheet loif m 154 `/fi//l z MM E PECK BY fue/N fz aww/sm@ June29,1943. w. F. PECKETAL V 2,322,878

EYE TESTING INSTRUMENT Original: Filed April 6, 1939 l2 SheetS-Shet 1lINVENTOR W/LL/HM E PECK HLB//Y H' vGR/PD/SHR June 29, 1943. w` F. PECKET Al. 2,322,878

EYE TESTING INSTRUMENT Original Filed April 6, 1959 l2 Sheets-Sheet l2el 55 65 es fzmk affyxxmq gxwg@ gxlygq 5s l e4 64 6l 6| 59 o z5, 66 66g64' 64 65 @mb @mln asm@ ffyxxm 64 lo 25 T 6| I 6+ 53 o so 66 lz 65 64 62/l e5 .3 eo

53 6| 59 65 a Y 64 6o 64 65 y' M M w 9mm 9.3mm 49.315231 wg, m 53 u 64el I 65 e; 64' I oo 630 60 SXIII@ 2 yXXIY@ fglXl 65 5 INVENTOH 4 WILL MMf PECK 6o lua/n' H. GRHD/ me Patented June 29, 1943 EYE TESTININSTRUMENT William F. Peck, Snyde r, and Albin A. Gradisar,

Buffalo, N. Y., assignors to American Optical Company, Southbridge,Mass., a voluntary association of Massachusetts Original applicationApril e, 1939, serial Ne.

266,360. Divided and this application September 1s, 1941,

` 12 Claims.

'I'his invention relates to improvements in ophthalmological instrumentsand has particular reference to an `improved form of instrument for usein determination of the lens values necessary to properly correctdefective or imperfect vision of various individuals.

This application is a division of our co-pending application Serial No.266,360, led April 6, 1939, now Patent 2,266,797, December 23, 1941.

One of the principal objects of the invention is to provide aninstrument of the above character whereby a minimum amount of the faceof the individual being tested will be covered by said instrument, withthe major portion of the operating mechanism of the instrument disposedin a direction away from the face so as to avoid the patients having aconfined or couped up feeling, which might cause fatigue and nervoustension, having undesirable reactionary effects on the tests performedby said instrument and which will permit ease of manipulation'of saidadjust' able parts without having the operators hands engage the face.

Another important object'of the invention is to provide an instrument ofthe above character whereby the lens cells may be placed in closerproximity with the eyes of the individual under test than has been usualwith most prior art instruments of this nature in the past, without theinstrument having undesirable contact with the nose or adjacent portionof the face of the individual during said test.

Another important object of the invention is to provide a cooperativelyfunctioning series of lenses computed as to curvatures and thicknesses,distance between the lenses of said series and position of said lensesbefore the eyes ,of the patient and associated mechanism forautomatically adding the individual lens powers before the eyes, bothspherical and `zylindric'al, whereby a reading of the total lens powercom` bine is given, thus making unnecessary `any calculations by theexaminer or practitioner` Another important object is to provide aninstrument of the above character with adjustable portions which areexceptionally free and easy to manipulate without undesirable annoyingcontact with the individual under test and with the associatedadjustable elements so correlated with each other and with the face ofthe patient or individual under test as to eliminate fogging of thelenses supported by said mechanism dueto condensation of the patientsbreath, etc., and to exclude to a major extent the accumulation ofSerial No. 411,422

dirt, dust, etc., on the lenses during the use of the instrument.

Another important object is to provide an instrument of the abovecharacter with associated units which may be quickly and easilydisassembled for possible repairs or cleansing, and so that units havingdifferent` characteristics may be interchanged with each other.

Another important object is to provide an instrument of the abovecharacter which is so constructed as to provide a relatively wide lieldof vision when looking through the test cells of said instrument and toeliminate to a great extent tubular type vision when looking throughsaid units.

Another object is to provide an instrument of the above character whichmay be quickly and easily adjusted and retained in desired positionbefore the eyes of the individual under test, and with the various meanswhich are to be manipulated duringisaid tests so disposed that they maybe easilymanipulated without interfering with thev iield of vision ofthe individual during said tests and Without the individuals directknowledge of said manipulations.

Another object is `to provide an instrument of the above character withrelatively simple and efficient corneal aligning means whereby theinstrument may be accurately located in position before the eyes of theindividual under test.

Another object is to provide improved details of construction and methodof assembly of the various parts of the instrument, wherebythe saidparts may be quickly and easily assembled or disassembled and will berelatively free and easy to manipulate during the use of the instrument.

Another object is to provide an instrument of the above character havingthe major portion of its lens cells angled with respect to the line ofdirect vision through the observation means of said instrument so thatthe Amajor portion of the instrument will be disposed in a directionaway from the face of the indiivdual under test.

Another object is to arrange the operating mechanism of the variousadjustable parts` correlated with the lens systems of said instrumentsbefore thel eyesof the individual under test, whereby the desired lenscombinations may be quickly and easily disposed in alignment with theobservation openings of `said units, and the ratio of movement of saidlens cells may be positively controlled, particularly in the cylindricalcomponent of the instrument, `whereby the cylinder axes of the lenses ofthe diierent series of said cylindrical components -will remaincoincident with each other when the units are in alignment with theobservation opening of the instrument and are rotatably adjusted.

Another object is to provide novel means and method oi assembling thelens elements with their retaining means during the manufacture of theinstrument.

Another object is to provide an instrument of the above character withall oi its operable parts disposed toward the front of the instrument.

provide novel means of supportment for supporting a near test cardwhereby` the said card may be moved in a horizontal and verticaldirection and in a direction toward and away from the instrument.

Another object is to provide an instrument of the above character with adurable and positive functioning construction with most of theadjustable parts confined within a housing, so as to provide a neat,compact appearance.

Another object is to provide the supporting discs or lenses of theinstrument with relatively large surface bearings whereby the desireddistance between the lenses of respective discs may bermaintained duringthe use of the instrument.

Another object is to provide simple and efiicient means of attachment ofauxiliary units.

Another object is to provide novel arrangement of cylinder cell controlwhereby the means for rotating the desired cylinder lens in alignmentwith the observation opening of the instrument and the axis controlmeans are concentrated at a single point of adjustment.

Another object is to provide novel means and method whereby the lenscells may be quickly and easily adjusted to zero position.

Another object is to provide an independently adjustable cell carrying aplurality of lenses separately of the main cells of the instrument whichmay be adjusted through a compound operating mechanism whereby a slightmovement of the adjustment control means will impart a relatively greatmovement to the immediate cell.

Another object is to provide scale and indicator means associated withthe separately adjustable portions of the instrument which may all beviewed from the front or examiners side of the instrument.

Another object is to provide novel means and method of automaticallylocating the various adjustable components in desired positionalrelation with respect to the observation openings of the instrument.

Another object is to provide novel headrests for instruments of theabove character.

Another object is to provide a systemfor indicating the total powervaluesl of the lenses in alignment with 'the observation openings of theinstrument, whereby the indicia indicating said power values will belocated adjacent the plane ofthe window openings in the 'respectiveunits ofthe instrument andwill be readily visible.

Other objects and advantages of the invention shall become apparent fromthe following description taken in conjunction with the accompanyingdrawings and it will be apparent that many changes may be made in thedetails of construction, arrangement of parts, and methods shown anddescribed without departing from the spirit of the invention asexpressed in the accompanying claims. We, therefore, do not wish to belimited to the exact details of construction, arrangement of parts, andmethods shown and described, as the preferred forms only have been givenby way of illustration.

Referring to the drawings:

Fig. I is a front elevation of the instrument embodying the invention;

Fig. II is a top plan view oi the instrument illustrated in Fig. I;

Fig. III is a side elevation of said instrument;

Fig. IV is an enlarged fragmentary front elevation of the supportingmechanism for the separate units, showing the means for changing thedistance between said units and for altering the angular disposition ofthe cells with respect to a line passing through the centers of theeyes;

Fig. V is a sectional View of Fig. IV;

Fig. VI is a fragmentary perspective view of the scale indicating theamount of adjustment for changing the distance between the units;

Fig. VII is a fragmentary partial sectional view showing the means forattaching the instrument to an instrument support;

Fig. VIII is a perspective view of the spherical lens system andassociated parts in disunited relation with each other;

Fig. IX is a rear elevation of one of the units of the instrument;

Fig. X is an enlarged sectional view of one of the units taken as alongline X-X, such as illustrated in Fig. IX;

taken as on line V-V Fig. XI is an enlarged fragmentary sectionalviewtaken as on line XI-XI of Fig. VIII and illustrating how the lenses aresecured in their supporting disc;

Fig. XII is an enlarged fragmentary sectional View taken as on lineXII-XII of Fig. VIII, illustrating how a relatively small diameter lensis secured to the lens supporting disc;

Fig. XIII is a perspective view of the cylindrical component of a unitand its associated operating mechanisms, showing the parts in disunitedrelation with each other;

Fig, XIIIa is a perspective View of the face of the disc to which it islinked on the side thereof opposite the side illustrated in Fig. XIII; v

Fig. XIIIb is a View similar to Fig. XIIIa of the other side of Fig,XIII with which it is linked;

Fig, XIV is a slightly enlarged sectional view taken as on line XIV- XIVof Fig, XIII, showing 'the various parts of the unit in assembledrelation with each other;

Fig. XV is a face View of an auxiliary unit;

Fig. XVI is a sectional view taken as on line XVI- XVI of Fig. XV;

Fig. XVII is an enlarged fragmentary sectional View taken as on linesXVII-XVII of Fig. XIII, showing the parts in assembled relation witheach other; f

Fig, XVIII is a face view of the power indicating, disc of thecylindrical component; y

Fig, XIX is a face view of various auxiliary components of theinstrument;

Fig, XX is an enlarged sectional view of each of said components takenas on lines XX-XX through said respective components as illustrated inFig. XIX; i i

Fig, IQII is a fragmentary perspective view of a part of the positionallocating mechanism which is associated with each of the respectiveauxiliary components;

Fig. XXII is a slightly enlarged fragmentary sectional View taken as online XXII-XXII of Fig. XIX, showing the operating mechanism of therespective auxiliary component;

Figs. XXIIIa to XXIIIm inclusive are fragmentary enlarged front `viewsof the recording window and associated recording indicia for thespherical system of the instrument, illustrating how the plus -sphericalpower readings are taken at different settings of said spherical units;

Figs, XXIVa to XXIVn inclusive are fragmentary enlarged front views ofthe recordingwindow and associated recording indicia for the sphericalsystem of the instrument, illustrating how the minus spherical powerreadings are taken at different settings of said spherical units; and iFig- XXV is a fragmentary enlarged sectional view taken as on line XXV-XXV of Fig. XIX,

Instruments of the character described are not new in the art, but muchdifiiculty has been encountered with such prior art instruments in thatthey could not be placed in a desired close relation with the averagerun of patients to be tested. In many instances the restrictions in thisrespect greatly reduced the eld of vision through the observationopenings of the instrument, introduced a danger of having the patientaccidentally engage the adjacent portions of the lens cells of theinstrument with resulting injury and discomfort, and also introduced aconningor shut-in eifect which resulted in an unfavorable reaction bythe patient and introduction of error inthe tests. Y i

Another diificulty with many; prior art `instruments, due to thisinability to position the lens cells in desired positional relation withrespect to the eyes, was that an optical error was introduced by theresultant change of distance of the lenses from the eyes, as broughtabout by said inability to position them in desired relatively closerelation with the eyes.

Another diculty with many prior art instruments of this nature was thatthe various operable parts of the instrument could not be manipulatedwithout danger of engaging and interfering with the patient under test,and in many instances the indicia by which the positional relation ofthe parts can be controlled were not y directly visible from the frontof the instrument.

Various other difficulties resided in the general construction of suchprior art instruments, such as loosely supported lens cells whichallowed the spaced relation of the lenses to move out of desiredrelation with each other during the ad justment of said cells, undesiredpoints 4of friction which introduced annoyingiand obnoxious noises whenthe cells were operated, exposure of the lenses to a collection ofdust,` etc., and to becoming fogged by the breath of the patient and thegeneral difficulty of manipulation and accurate adjustment of thevarious components of the instrument. Y

It, therefore, is one of the primary objects of the invention to`overcome all of the above difficulties in such a manner that theresultant Vinstrument has all of its components so related as to havefree and positive movement relative to each `other and yet be supportedin compact l 3 `relation with each other, so as to permit the instrumentto be positioned in desired close rela# tion with the eyes of thepatient, regardless of facial contour, particularly spaced relation ofthe lens cells relative to said eyes, and to obviate the conning shut-ineffect introduced by most prior art instruments of this nature. i

The above, taken in conjunction with the remaining objects previouslyset forth, are the novel and characteristic features of the invention.

Referring more particularly to the drawings, wherein like characters ofreference designate like parts throughout the several views, the deviceembodying the invention comprises a pair of spaced units I and 2, eachattached as by screws or thelike 3 to downwardly projecting tongues 4,carried by an adjustable head 5; i

The units I and 2 each comprise a spherical component 6 as illustratedin Figs. VIII and X and a'cylindrical component 'I as illustrated inFigs. )HIT and XIV.

'Ihe spherical component; 6 is contained within a housing 8 asillustrated in Figs. I, II, III, IX and X and the cylindrical component'I is contained within a housing 9 as illustrated in Figs.` I, II, XIII,and XIV.

One of the outstanding features of the invention resides in theparticular shape and relation of the spherical housings 8 as illustratedin Fig. 1I.

I1; is to be noted that each of these housings has the shape of afrustum of a conewiththe axes;` I0 of said conical housings so disposedas to intersect each other at the front or examiners side of theinstrument and to position the outside conical surfaces of the housingsin such a relation lthat both surface portions II adjacent the eyepositions will lie along substantially a straight line I2 in a`direction transversely of the instrument in such a manner that avertical plane tangent to both of said surface portions II will besubstantially perpendicular to the lines of straight ahead vision of theeyes of an individual under test, as indicated by the dot and dash linesI3 and will be substantially parallelto a vertical plane tangent withthe corneas of said eyes, as illustrated by the dot and dash lines I3.'I'his causes the axes of sightl or observation openings I5 in saidhousings 8` to be substantially coaxial with the lines of straight aheadvision I3. II, IX and X. The axes of the sight or observationy openingsI5 are substantially parallel with each other and when' in correctposition before Vthe eyes are coaxial with the line of straight aheadvision of said eyes. This constructionof housing enables the units I and2 to be tted in relatively close relation with the face. This is due tothe fact that the tapered walls II, as they progress upwardly anddownwardly from the sight or observation openings I5, curve in adirection away from the face, thereby allowing said housings to bepositioned in normally closer relation with the eyes without danger ofabnormal engagement with the face of the individual under test. Thiscurving away of the tapered or conical Walls II of the housings 8, inaddition to the angular disposition of said housings relative to eachother, l

as illustrated in Fig. II, obviates the introduction of a confining orcouped in effect to the patient and also provides clearance at the sidesof the nose, so that the said housings may be adjusted in closerrelation with each other than would be possible if they were not soangled. This also affords the examiner clear visionlof the patients eyesduring the use of the instrument and during the initial positioning ofthe instrument before the eyes. The eye of the examiner isdiagrammatically illustrated at I in Fig. II.

The particular angle of disposition of the respective housings 8 isquite critical as to the resultant overall width and thickness oi theinstrument and the size of lenses required in the instrument. It hasbeen found that usable instruments may be constructed within cone anglelimits of from approximately 10 to 30, as may be indicated by the lesserangle formed by the meeting of line I0 and an extension of line I3 inFig. II.

The most desirable angle, however, is approximately 18. This angleproduces the desirable instrument from the standpoint of size,construction and face clearance. With this optimum angle of 18 the cellssupporting the spherical lenses will have a desirable cone angle and thecells supporting the cylindrical lenses will have approximately half ofsaid Cone angle.

Increasing of the cone angle increases the resultant thickness of theunits and thereby introduces a tunnel eifect when looking through theobservation openings of the instrument. This increase of cone angle alsocauses a rapid increase of overall width of the instrument. Decreasingof the cone angle from the 18 results in loss of face clearance and alsoincreasing the couped in effect.

For ease of description we will first consider only the left unit I.

The spherical component 6 of said unit as illustrated in Figs. VIII andX, comprises a plurality of discs Il', I3 and I9. In the disc I'I thereis mounted a plus series of spherical lenses graded in steps of quarterdiopters ranging from +.25 to +1.75 and a minus spherical series gradedin quarter diopters ranging from .25 to 1.00. The disc I8 has a seriesof relatively strong spheres 2I therein with a plus seriesgraded insteps of three diopters ranging from +3.00 to +1500 and a minus vseriesalso graded in steps of three diopters ranging from 3.00 to 18.00.

It is to be noted that each of the discs I1 and I0 is cupped to a shapesimulating the shape of the housing 8, with the cupping such as todispose the axis of each lens, when in alignment with the observationopening I5, in substantially coaxial relation with said o-pening andcoaxial with the line of straight'ahead vision through said opening whenin correct position before the eyes of the patient. Contained withinsaid spherical component there is a disc I9 having a plurality ofIopenings 22 therein. These openings contain a -.12 diopter sphere 24, ablank opening 25, and a +.12 sphere 26. The disc i9 is also providedwith a plurality of openings 21 in which is mounted a 6.0 prism 28, a10.0 prism 29, a 15.00 prism 30, and a pinhole disc CilI. It is to beunderstood that other lenses of different characteristics may be used ifdesired. y

The housing 8 is provided with a stud 32 rigidly secured in a centralopening in said housing. The stud 32 is provided with a flanged portion33 which engages the botto-m surface of a shouldered recess 34 formedcentrally and internally of said housing. The stud 32 is retained in theopening in said housing by means of a screw or the like 35. This screw35 also functions as retaining means for holding a corneal aligningattachment 35 on the rear of the housing and for holding a blade spring'member 3i between said housing and said corneal aligning device.

Within the shouldered recess 34 internally of red glass 23,

tion with the gear 39.

vlike 44.

the housing 3 and on the flanged portion 33 of the stud 32 there `ispositioned a gear member 38. The gear member 38 is in constant mesh witha gear 39 also rotatably supported within the recess 34 by 'a screw orthe like 40. The screw cr the like 40 also supports a gear 4I insuperimposed rela- The said gears 39 and 4I are secured to each other byscrews or the like 42 so as to rotate as a single unit. The gear 38 issecured to a bearing sleeve 43 by screws or the The said bearing sleeve43 is rotatably mounted on the stud 32. The bearing sleeve 43 forms 'abearing on which the discs I8 and I9 are rotatably mounted. The disc I9has a protrusion 45 on which is tted a gear 45. The gear 46 is securedto the disc I9 by screws or the like 41 and is in constant mesh with thegear 4I. The disc I9 is provided with an opening 43 through which theperson assembling the unit may view the gears 4I and 46 so that they maybe assembled in proper relation with each other.

The opposed end of the bearing sleeve 43 has an arm 49 secured theretoby screws or the like 50. A suitable lock pin 5I is adapted to anchorthe arm 49 in desired relation with the sleeve 43. The arm 49 has athumb piece 52 thereon which also provides an indicator member, as willbe described more in detail hereinafter.

It is to be noted that upon manipulation of the thumb piece 52 to rotatethe arm 49, the said arm being integrally connected with the sleeve 43will impart a simultaneous movement to said sleeve. This movement of thesleeve 43 is transmitted through the integrally connected gear 35i tothe gears 39 and 4I, which, in turn, impart 'a rotary movement to thegear 45. The gear 45, being integrally connected with the disc i9, willcause said disc to rotate when the thumb piece 52 is moved. The purposeof the train of gears 38, 39, 4I and 43 is to cause a slight movement ofthe arm 49-to impart a relatively great rotar;1 movement to the disc I9,so'that the openings 22 and 21 in thedisc I9 may be selectively movedinto alignment with the observation opening I5. The thumb piece 52 onsaid arm is adapted to cooperate with a scale 53 on the face of thehousing 8, as indicated infFig. I. The scale is so graduated that theindicator 5?. may be moved to selective positions thereon and therebymove the desired openings 22 and 2l into alignment with the observationopening I5.

lIhe disc I8 is provided with a shouldered boss 54 which provides abearing on which the disc I'! is rotatably supported and also providesmeans on which a scale plate 55 is secured as by screws or the like 53,

The disc I'I, as shown in Fig. VIII, is provided with spaced concentricscale indicia 5l and 58. These indicia indicate fractions of a diopterwhich are added to the correction in alignment with the observationopening I5 when the disc Il is progressively rotated.

It is to be noted that these scale indicia are graduated in quarterdiopter steps. One of said scales, preferably the outer scale 53, hasindicia of a given color indicating minus values, while the innerconcentric scale indicia 5l are preferably of another color, indicatingthe plus quarter diopter Values.

It is to be noted that each of the scales is divided into three sectorsranging from 0 to '75 in quarter diopter steps. The scale plate leftunit I has a plurality of openings 59 therein in concentric relationwith the effective center of said plate and adapted to cooperate withthe ine5 for the e ner scale 5'I and has a portionvof its periphery cutaway to provide 'angularly disposed edge apertures 60 concentricallyarranged with the effective center 63 of said plate and at such a radiusas to cause portions of the plate adjacent the edge apertures 68 andallow only the outer scale 58 to be visible.

The openings 59 are arranged inspaced progression concentrically withrespect to the effective center 63 of the plate 55 and each has scaleindicia 6| associated therewith. The said scale indicia 6I arepreferably white and indicate the total plus power values of the` totalcorrection in alignment with the observation opening I5 as introduced bythe spherical lenses of the respective discs I'I and I8, eitherseparately or jointly. The said indicia range from to 16 inclusive. Eachof the angularly disposed edge apertures 60 are provided withscaleindicia 62, Apreferably colored red, and indicating the total minuspower values of the spherical lenses of the discs II and I8 which are inimmediate alignment with the observation opening I5.

It is to be noted that lenses carried by the disc I I cooperativelyfunction with the respective lenses of the disc I8 and are so arrangedthat the power values of the lenses moved into alignment with theobservation opening I may be built up progressively in steps of quarterdiopters. The readings are taken through a window opening 64 formed inthe front of the housing 8. The quarter diopter value readings areindicated in Figs. XXIIIa to XXIIId, starting from 0.00 to 0.75. As thedisc I`I is rotated to advance one step further, the full power readingof 1.00 will be indicated as illustrated in Fig. XXIIIe. These readingsare of the plus power values. It is to be understood that `furtherrotation of the disc I'I causes the reading through the window openingas illustrated in Fig. XXIIIe to progressively change from 1.00 to 1.25,1.50 to 1.75, whereupon the discs I1 and I8 are simultaneously rotatedto move a lens contained in the disc I8 into alignment with thevobservation opening I5. This lens in combination 4with the lenscontained in the disc I'I gives a total +2.00 power, as indicated inFig. XXIII. This total +2.00 power is derived through the alignment of a+3.00 lens carried by the disc I8 and a +1.00 lens carried by the disc II with the observation opening. The disc I8 remains stationary and thedisc I1 is then further rotated to introduce the remaining progressivelyarranged quarter diopter steps of +0.75 to +0.25, whereupon the blankopening in the disc I'I is aligned with the observation opening I5 andonly the +3.00 lens will be in alignment with said observation opening.This is indicated by the movement of the .00 indication into alignmentwith the full +3 value indication of Fig. XXIIIf. Further rotation ofthe disc I'I will introduce progressively arranged .25 diopter steps of+.25 to +1.75, which steps, in combination with the existing +3.00, willgive totals of +3.25 to +4.75 respectively. Further combinations areprogressively built up in quarter diopter steps in a similar manner.. asthat set forth above until the maximum +16.75 valuefis reached. Theminus spherical lens values are built up in a similar manner to `givetotals ranging from 0.00 to +l9.00 diopters.

In the left unit the plus quarter diopter value readings are takenthrough the opening 59 and the full diopter values from the scale 6Iadjacent said openings, said totals are diagrammatically illustrated inFigures XmIIa to XXIIIm.

to overlap the inner scale 5`I 4immediately distinguish the minus scale.

5 The minus readings are as illustrated in Figs. XXIVa to XXIVn. Thecooperative function of the edge apertures 60 and the window opening 64produces a scale opening 65, in which the minus quarter diopter valuesare visible. The full power values of the minus component in alignmentwith the observation opening I5 is indicated by the scale indicia 62adjacent said edge apertures 60. The minus scale indicia 62 andassociated quarter diopter indications visible through the opening 65are preferably red, so that the operator may It is to be noted that thereadings are in a progressive manner simulating those of the pluspowers, so that the quarter diopter readings as indicated in Figs. XXIVbto XXIVd are in step by step progression as indicated at 66. The +1.00value is determined by the alignment of the .00 with the +1 indicationas indicated at 6'I in Fig. XXIVe. When this point is reached both ofthe discs I1 and I8 are simultaneously rotated, whereupon an additional+`1 indication as illustrated at 68 moves into alignment with the windowopening 64 and a ,+.25 indication adjacent said +1 also moves intoalignment with the Window opening 64 as illustrated at 69 in Fig. XXIVf.The powers are then reduced in step by step progression until a +4.00reading is visible in the window opening 64, whereupon both of the discsI'I and I8 are again rotated simultaneously to bring a +4.25 value intoalignment with the observation opening I5. This being the result of a+6.00 lens in disc I8 and a +1.75 lens in disc I'I. This value isindicated at 'Ill in Fig. XXIVg. This procedure is repeated until themaximum value of 19.75 is reached. `The plus values of both discs II andI8 are increased positively by rotation in one direction and decreasedpositively by rotation in the opposite direction. It is to be noted byreference to Figs. I, II and VIII that the discs II and I8 are providedwith corrugated peripheral edges which extend outwardly of the housing 8at opposite sides ofthe units I and 2, so that the said discs I'I andI8.may be engaged and be manually operated by the examiner. The readingsthrough the window openings 64 give the total spherical lens powervalues, plus or minus, of the immediate lens system in alignment withthe observation opening l5.

The unit 2 on the right side of functionally is generally similarscribed above.

the instrument to unit I de- It is to be noted, however, that theapertures 59 and 68 of the plate, corresponding to plate 55, are movedinwardly toward the center of said plate one position.

These apertures are moved inwardly because on the right side of theinstrument, thatis in unit 2, the whole numbers appear away from thecenter of the plate with respect to the decimal fraction numbers, Whileon the left side, or in unit I, the whole numbers appear toward Vthecenter of the plate with respect to the decimal fraction numbers. Thefigures 51 and 58 in unit 2 are moved an amount corresponding to theshift of position of the respective apertures 59 and 60. It is to benoted that the order of the lenses is varied accordingly, so that thedesired progressive values may be built up in the sight opening I5 ofsaid unit.

It is to be noted that the plate 55 carrying the scale indicia 6| and 62is located directly beneath the wall of the housing having the windowopening 64 therein and are ina plane adjacent the plane of said window.This plate 55 is relatively thin so that the indicia 5'I and 58 on thedisc I'I 6 are also relatively close to the plane of the window opening.Due to this factl the readings may be easily taken through said window.There is practically no depth resulting in undesirable side shadows andrequiring looking directly into said window openings in order to takesaid readings. With the present arrangement the indicia are visible atrelatively great side angles of observation.

To facilitate ease of manipulation and to retain the lenses 20 and 2|carried by the respective discs I'I and I8 in proper computed spacedrelation with each other, there is provided a ball race 12 adjacent therespective series of lenses, that is, at a. point substantially spacedfrom themain sleeve bearing 83 and boss 58 on which the disc I1 isrotatably mounted.

It is to be noted also that the discs I8 and I9 each have contiguousside bearing surfaces 13 adjacent the center thereof and are also eachprovided with spaced contiguous bearing surfaces 14 adjacent therespective series of lenses carried by said discs. The disc I9 andhousing 8 lalso have contiguous side bearing surfaces 15 at a pointspaced outwardly from the central bearing.

This arrangement provides a smooth functioning assembly and prevents anyundesirable axial movements between the discs and the housing andpositively supports said discs in desired spaced relation with eachother.

Each of the discs I1, I8 and I9 are provided with a plurality of spacedindents 16, 11 and 18. The indents 16 of the' disc I1 cooperativelyfunction with the bent endy19 of a vspring iinger 80 carried by thehousing 8. The indents 11 of the disc I8 cooperatively function with thebent end 8| of an additional spring finger carried by the housing 8 andthe indents 18 of the disc I9 cooperatively function with a rollermember 82 carried by a spring finger 83 also supported on the housing 8adjacent the ngers. The purpose of these indents and respective springfingers is to provide indexing means whereby the lenses of therespective series will be positioned in proper aligned relation with theobservation opening I5.

The tension of the spring fingers cooperatively functioning with 'theindents 18, 11 and 18 may be varied by adjustment of the screw members84.

The various lenses of the series carried by the disc I1, as illustratedin Fig. II, are mounted in said disc through the provision of `ashouldered lip 85 in each of the openings in said disc. The lenses areadapted to rest on the shouldered lip and are preferably bevelled, asillustrated at 86, so as to receive the retaining rings 81. The rings B1are provided with a tapered edge surface adapted to cooperativelyfunction with the tapered edge surface 88 of the lenses and are held inengagement with said lenses by screws or the like 88, so that th'elensesmay be quickly and easily secured in the disc or removed therefrom. Thelenses of the disc I8 are similarly held therein. It is to be noted,however, by reference to Fig. XII, `that in some instances, particularlyin instances where a strong plus power lens, such as illustrated `at 89is used, and the said lens cannot be made as large in diameter as thelenses 2| or 20, an auxiliary supporting 'ring 90 is provided. .The ringis provided with a shouldered lip 9| simulating the lip 85 and 'the lens89 is held on said lip by spinning over -a flanged protrusion 92 onsaidauxiliary ring 90. The ring 90 and attached lens 89 are secured inengagement with the shouldered lip 85 in va r'nanner similar to -1.00and the nrst mentioned spring described in connection with the lensillustrated in Fig. XI, that is, by means of a retaining ring 81 andscrew members 88. In this instance the auxiliary disc is provided with atapered contour edge adapted to cooperatively function with the taperededge surface of the ring 81.

The cylindrical component as illustrated in Figs. XIII, XIV, XVII andVIII, is contained in an auxiliary housing 9 secured to the front of thehousing 8. This housing 9 is best illustrated in Figs. I, 1I, III and IXand is attached to the front of the housing 8 by screws or the like 93extending through suitable aligned openings formed in flange-like lips94 on said housing 8 and similar flanged lips 95 formed on the housing9, see Fig. XIII. The various openings through which the attachingscrews 93 extend are illustrated at 98. The openings 98 are preferablyprovided with a threaded bore to receive the threaded portions of thescrews 93.

Each cylindrical component comprises a pair of discs 91 and 98. The disc91 contains a series of relatively weak power cylinders 99 arranged inquarter diopter stepsl ranging from 0.25 to disc 98 has a series oflenses |00 graded in 1.25 steps ranging from 1.25 to 5.00. It is to beunderstood, however, that these lenses may be plus cylinders if desired.This is to satisfy the requirements of the trade. In some instances theexaminers prefer the use of minus cylinders, while in other instancesthe examiners prefer the use of plus cylinders, so that this phase ofthe invention is optional and the series of lenses carried by therespective discs 91 and 98 may be either plus or minus powers asdesired. Each of the lenses 99 and |00 of the respective series carriedby the discs 91 and 98 are rotatably supported in said discs.

It is to be noted by reference to Fig. XIV that the lenses 99 or |00, asthe case may be, are respectively secured in annular-like supportingrings IOI. Each of these rings is provided with a shouldered lip` |02 onwhich the immediate that previously lens is rested and are each providedwith a ianged protrusion |03 which is spun over to secure the lens insaid supporting rings |0I. The rings l0| are each provided with a ange|04 having gear teeth |05 out in the periphery thereof. The rings |0Iare each `providedwith a shouldered portion |06 which rotatably engagean annular internal lip |01 formed in the respective openings in thediscs 91 and 98. The supporting rings |0| are secured to the internalannular lipV |01 by means of the retaining rings |08 held in securedrelation with the supporting rings I8I by outwardly spun annular lipportions |09 formed on said ring. The gear teeth |05 of the supportingrings in the respective discs 91 and 98 all mesh with a gear IIO. Thegear |I0 is rotatably supported in a shouldered recess III formed in theinner central surface of the disc 98. The disc 98 is secured to a hollowspindle II2, which, in turn, is rotatably supported by a stud |I3carried by the housing 9. The stud I I3 is provided with an integralflange II4 which is seated within a recess |I5 formed in the housing 9and is rigidly secured therein by a screw IIB.

It is to be understood that the pin ||3 has a press fit with a suitableattaching opening |'|1 formed in the housing. The hollow spindle |I-2has a reduced threaded extension I'I8 on which the disc 98 is positionedand secured by means of a clamp nut II9, so that the hollow spindle I I2and disc 498 are rotated on the Stud I3r as an integral unit. The hollowspindle ||2 to which the disc 98 is integrally attached, adjacent oneend thereof, has a gear |2| secured thereto adjacent its opposite end.The gear 2| meshes with a gear |22 secured to a Geneva wheel |23. TheGeneva wheel is rotatably supported on a central bearing |24 secured tothe housing 9 by a screw or the like |25. The Geneva wheel |23, adjacentits end opposite the gear |22, has a star wheel flanged portion |26adapted to be engaged by a pin |21 carried by the disc 91. The disc 91is carried by a sleeve |28 rotatably supported on a tubular sleeve |29which, in turn, is rotatably mounted on the inner hollow spindle 2. Thesleeve |28 is provided with a pin |30 tted within a slot |3| formed inan integral boss on the disc 91 and also has an integral gear portion|32 thereon. As shown in Fig. XIII, the gear 32 is in constant mesh withan idler gear |33 pivotally attached at |34 to the housing 9. The idlergear |33 is in constant mesh with a gear |35 attached to a spindle |36having a thumb wheel |31 thereon. The spindle |36 also has a gear |38secured thereto, by a screw or the like |39, which is in constant meshwith the gear disc |40. The gear disc |40, as illustrated in Fig. XVIII,is provided with scale indicia |4| which is visible through a windowopening |42 in the front of the housing 9. See Fig. I. The disc |40 isrotatably supported on the housing 9 as illustrated at |43, and ismerely for the purpose of indicating the power of the cylinder system inalignment with the observation opening |5. It is to be noted that theplane of the surface of the disc |40 having the scale indicia thereon isadjacent the plane of the window opening |42 so that direct vision ofsaid indicia is facilitated.

It is to be understood that the housing 9 has an opening in alignmentwith the observationA opening of the housing 8. See Figs. I and XIII. Itwill be seen, therefore, that through rotation of the thumb wheel |31,the gear |35 is rotated and the idler gear |33 is simultaneouslyrotated. The gear |33, being in constant mesh with the gear |32, willimpart a rotary movement to the sleeve |28. The sleeve |28 and disc 91having a pin and slot connection |30 and |3|, will, in turn, cause saiddisc 91 to be rotated. The rotation of the disc 91 will successivelyalign the lenses 99 with the observation opening |5.

It is to be noted that when the disc 91 is rotated the gear portions |05of the lens supporting rings |.0|, meshing with the gear |0, will berotated in said disc 91. This is due to the fact that the gear I |0 isheld stationary during said rotation of the disc 91. The gear ||0 isconnected to the tubular sleeve |29 by a pin |45 and is, therefore, heldstationary through said connection during the rotation of the disc 91.This causes the axes of the lenses 99 carried by said disc 91 to assumea definite meridional position when in alignment with the observationopening I5. The pin |21, during the rotation of the disc 91,intermittently engages the star wheel |26 at every complete cycle ofmovement of the disc 91. The star wheel |26 in turn rotates the gear |22which is in constant mesh with the gear |2| and thereby imparts a rotarymovement to the hollow spindle 2, having the disc 98 rigidly attachedthereto adjacent its opposed end, causes the said disc 98 to move anamount sufficient to advance a lens |00 carried by said disc intoalignment with the observation open'mg. The disc 91 then rotates onecomplete cycle of movement, whereupon the Geneva mechanism will to therotation of the lenses 7: advance another lens 00 into alignment withthe observation opening.

It is to be understood that the axes of the4 lenses 99 and |00 arecoincident with each other when the said lenses are aligned. Due to the.meshing of the gear portions |05 with the gear 0, the axes of therespective lenses in alignment with the observation opening will remaincoincident with each other'when the respective lenses 99 and |00 arerotated. The sleeve |29 is provided with a flange-like gear |46 which isin constant mesh with a gear |41 on a tubular member |48 rotatablymounted in the observation opening I 5. This tubular member |48 is toprovide means for receiving auxiliary lenses such as illustrated in.-Figs. XV and XVI.

It is to be noted that the tubular member has a ring |49 secured theretoby screws or the` like |50. The ring |49 is provided with an opening |5|in which a locating pin |52, carried by the auxiliary attachments, isadapted to be positioned. rI'he auxiliary attachments have annularlikeportions |53 in which the auxiliary lenses |54.l are secured. Saidannular-like portions are,- adapted to be positioned in telescopedrelation, with the tubular member |48 with the locatingv pin |52functioning to align lenses 99 and |00 respectively.

It is to be noted that when the tubular sleeve;- |29 is rotated, thegear portion |46 thereof, in mesh with the gear the tubular member |48,will rotate the auxiliary lens simultaneously.

99 and |00 with respect to their supporting discs 91 and 98. Thisrotation is to alter the direction of the axes of the lens system beforethe eye and is brought about the manipulation of a thumb wheel |55mounted in adjacent concentric relation with the thumb wheel 31. Thethumb wheel 55 is carried by a hollow shaft |56. The hollow shaft |56cured to the housing The gear |60 is in constant mesh with the gear |46on the tubular sleeve |29. It will be noted, therefore, that when thethumb wheel |55 is,4 rotated, the gear |59 meshing with the idler gear|60, which, in turn meshes with gear |48 will rotate the tubular sleeve|29. The tubular sleeve |29 will, therefore, impart a rotation to theintegral gear portion |46 and to the gear ||0 through the pin connection|45. The gear ||0 will simultaneously rotate the lenses 99 and |00 andthe gear |46 will also simultaneously rotate the tubular member |48 andthe auxiliary lens supported by said tubular member.y In this immediatealignment with cooperatively function with the protraetor scale |63.

'tion in the periphery With the above arrangement, it will be seen thatas the disc 98 is rotated through its connection with the thumb wheel|31, the lenses |99 in said disc may be successively aligned with theobservation opening of the unit and that at the completion of each cycleof rotation of said disc 98, the Geneva mechanism will automaticallyfunction to advance the disc 91 an amount sun cient to move another lensof said disc into alignment with the observation opening.

The discs' 91 and 98 are each provided with a plurality of indents |65and |55 in spaced relathereof. These indents |65 and |65 are adapted toengage respective roller members |61 and |53 carried by spring arms 69.The rollers |51 and |68 are adapted to cooperatively function with theindents |65 and |56 to automatically and positively position the lensesin alignment with the observation opening.

To aid in retaining the auxiliary attachments, such as illustrated inFigs. XV and XVI, internally of the tubular memberl |48, there areprovided friction spring bars |19. See Figs. Xll and XIV. These springbars |19 are adapted to exert a pressure on the side surface of theannular portions |53.

It is to be noted that the discs 91 and 98 are cupped so as to cause thelenses 99 and |99 to assume a coaxial relation with the line of sightthrough the observation openings.

To provide a smooth functioning connection, a spring washer |1| ispositioned between the thumb wheel |55 and the adjacent supportingmechanism.

To insure that the lenses, maintain a vfixed axis as the discs 91 and 98are rotated, there is supplied an anchoring friction element 3|9. Thisfriction element 3|@ is between the housing 9 and the gear |59. Thefriction washer |1| is. adapted to urge the gear |59 into bindingrelation with the friction element 3||| and the said gear is therebyfrictionally held in non-rotary relation with respect to the housing 9.The gear |59 being in constant mesh with the gear |69 will hold saidgear stationary and also hold the associated lens rotating mechanismstationary.

It is to be noted that the shoulder bearing member |6| may be adjustedby loosening the screw |62 so that the gear members may be positioned inrelatively intimate meshed relation with each other to eliminatebacklash. This adjustment is retained by thereafter tightening the screw|62. Similar arrangement is provided throughout the instrument to takeup backlash in the gear assemblies.

It is to be noted that the scale |4| is graduated in quarter dioptersteps and is such that it covers a complete range ofy cylinder powersand indicates the actual power of the cylindrical lens system before theeye, regardless of whether it is plus or minus. If the minus lenses areused it is assumed that the indications are minus powers, and viceversa.

The cylinder component may be disassembled for lens cleaning and forinterchanging plus and minus cylinders by removing the cylindricalhousing unit from the instrument. This is accomplished by removing thescrews 93. The dials 91 and 98 are in turn disassembled by removal ofthe nut ||9. To facilitate the dial removal the index rollers |61 and|68 are removed from contact with periphery of discs by removing screw3|| and swinging the spring support block |98 and |54 will asaasrs onthe pin 3|2. This releases the tension of the spring arms |59.

To assure proper axial relationship of the cylinder lenses 99 withcylinder axis scale |63, when reassernbling the annular supporting ring||l| are supplied with indicia a to match with corresponding indicia bon the disc 91. The gear ||0 and the disc 98 are similarly provided withindices c and d. It is to be understood that these marks are used inconjunction with the proper scale setting of |63. This setting beingpreferably the zero position.

As previously described, the units and2 are separately attached todownwardly projecting tongues 4. The tongues 4 fit within slotted webs|12 carried by the housing plate 9. The downwardly projecting tongues 4are each carried by slide members |13 and |14. See Figs. IV and V. riheslide members are slidably supported in a slide block |15 pivotallysupported by bearing members |16 carried by the yoke |11. The bearingmembers |16 are locked with said yoke by screws or the like |18. A faceplate |19 slidably supports the slide members |13 and |14 internally ofthe slide block |15. The frictional pressure of said plate on said slidemembers may be controlled by adjustment of screws or the like |89. Theslide members |13 and |14 are slotted to receive a shaft 18| rotatablysupported in the bearing members |16. The shaft |8| has a hand wheel |82thereon and has a' pinion 83 centrally thereof immediately positionedwithin the slotted portions of the slide members |13 and |14. The slidemembers |13 and |14 are respectively provided with rack members 94 inconstant mesh with the pinion |89, so that when the pinion is rotated bymanipulation of the hand wheel |82, the said slide members |13 and |14may be moved longitudinally of the slide block |15 and in this mannerthe units and 2 carried by the downwardly projecting tongues 4 of saidslide members will be moved outwardly or inwardly relative to each otherso as to change the clistance therebetween. The plate |19 is providedwith a window opening |85, through which is visible a scale |85 carriedby the slide member |1fl. The scale |85 is secured to the slide member|14 by screws or the like |91. The scale |86 is adapted to cooperativelyfunction with an indicato-r mark |88 on the other of said slide members.|This scale and indicator means is adapted to determine theinterpupillary distance between the observation openings of therespective units, so that the spacing between the centers of the openingmay be set substantially to the distance between the pupils of theimmediate patient to be tested.

The ends 0f the block |15 and plate |19 are covered by shield-likemembers 399 so as to produce a relatively smooth outer contour surface.It is to be understood that the edges of the shieldlike members are inflush relation with the upper. lower, and side surfaces of the block andPlate. The shields 399 are secured in position by screws or the like3H). The shield on one end forms backing means Vfor the coil spring |96so that the plunger and spring |96 may be inserted into the longitudinalbore in the upper portion of the block |15 and sealed therein by theadjacent plate 389. A similar bore was provided on the opposite side inwhich the spirit level |91 is positioned. This bore is likewise sealedby the adjacent plate 309.

It is to be noted that spacing washers 3H are provided between thebranches of the yoke |11

